Improvement in crutches



varmpit-rest.

UNITED STATES PATENT OEErcE.

- JOHN HABTMAN, JR., OF PHILADELPHIA, PENNSYLVANIA.

IMPROVEMENT IN CRUTCHES.

Specification forming part ot' Letters Patent No. 42.473, dated April 26, 1863 antedated December 2.2, 18 3. i

To @ZZ whom it may concern..l

Be it known that I, JOHN HARTMAN, Jr., of the city and county ot' Philadelphia, and State of Pennsylvania, have invented a new and useful Improvement in Crutches; and I do hereby declare that the following is a full, clear, and exactdeseription ofthe construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, in which- Figurel isa perspective view of an improved Fig. 21s a vertical section of the same. Fig. 3 is aperspective view of' a guttapercha tube, A, which constitutes the support l'or the armpit. Fig. 4 is a perspective view ot' one 0f thejams B.

Lilie letters in all the figures represent the same parts.

The nature of my invention consists in combining ay tube of gutta-percha, 0r an equivalent substance, with the statt' or frame ofthe crutch in such a manner as to form a yielding and easy rest for the armpit.

To enable others skilled in the art to make and use my invention, I will proceed to deszribe its construction and operation.

A is a tube, which I make of guttapercha, or other equivalent substance.

B B are metallicjaws, between which the said tube is secured by means of the screws C C. The said screws are of conical form, as representediin the drawings, (see Fig. 2,) and there are conical openings cV a. in the jaws B B, in which the ends of the tube are expanded by the force of the said screws. By this ar rangement the tube 'is securely held in its place; but in order to fasten the ends of the tube more perfectly I construct the screws O C with annular grooves b b, into which4 the I former con tract when forced into their sockets, as represented in Fig. 2. Thejaws B B have openings d d, into which the prongs of the frame ot' the crutch are inserted.

There may be a cross-rod combined with the jaws B B in any convenient manner to add stiffness to them, it' desired, or the jaws may be made in a single piece. It will readily be seen that the tube A will yield to the pressure exerted upon it by the weight ot' the body sufficiently to accommodate itself to the form otthe armpit, and thus give au easy support to the latter.

Having thus fully described the construction and operation of my improvement in crutches, what I claim therein as new, and desire tosecure by Letters Patent, is-

l. Constructingandcombiningwiththestai or frame of thecrutchatube of guttapercha, or other equivalent substance, to forni a yieldin g and easy rest for the armpit, substantially as described.

2. The combination ofthe tube A with the jaws B B by means of the conical screws C C, or their equivalent, substantially in the manner and for the purpose above set forth.

In testimony that the above is my invention I have hereunto set my hand and affixed my seal this 16th day of November, 1863.

J. HARTMAN, Ju.. [L s] Witnesses: V

\ STEPHEN Us'rIoK, J AMES MGCAHEN. 

